Gastric cancer is a highly aggressive and lethal malignancy. On a global basis, gastric cancer is the second leading cancer cause of death. Every year nearly 700,000 people die from the disease. Asian countries, such as Japan and Korea, have particularly high incidents of gastric cancer. For example, it is estimated that gastric cancer causes more than 16% of the male deaths in Korea and Japan.
Both heredity and environmental factors play roles in the development of gastric cancer. First-generation offspring of gastric cancer patients and people with blood type A are at increased risk of gastric cancer. There also appears to be a correlation between a relatively high salt diet and gastric cancer. A high incidence of gastric cancer is reported in countries in which salted fish is a dietary staple such as Korea, Japan, Finland, and Iceland.
In addition to heredity and diet, infection with Helicobacter pylori (Campylobacter pyloridis) is a risk factor for developing gastric cancer.
Gastric cancer may exhibit a wide range of symptoms and is often confused with other more benign digestive illnesses. Gastric cancer often goes undiagnosed until detected in an advanced state thereby limiting ameliorative treatment options.
Currently, a diagnosis of gastric cancer is made by gastrointestinal X-ray examination and endoscopic examination both of which have particular limitations. X-ray examination can miss small lesions while endoscopy requires the patient to undergo anesthesia. Both of these methods require highly trained specialists and are impractical as a general screening method.
There remains a need for a rapid, minimally invasive screening assay for gastric cancer.